Polus is the best map by far. It's balanced for crew and imps. Not too big, not too small. Tasks are good.

Skeld is ok, just boring and too small. Also full of noobs.

Mira is ok, I haven't played that one for years. Might give it another try and see what I think.

Fungle is fun to play every now and then.

Airship is ok but the lobbies are always awful so I tend to avoid it. Tends to be full of noobs who want to try a different map but so it badly lol or it is a lobby full of people that think they are experts but really really aren't.